Actualité - Breast cancers

COVID-19 and breast cancer


No argument for excess mortality in patients undergoing breast cancer treatment and infected by the virus.

Cancer du sein et chimiothérapie

In the first worldwide study conducted on patients undergoing treatment for breast cancer at Institut Curie, and also infected by SARS-CoV-2, doctors are reporting that there is no major apparent excess mortality in women infected by the virus and undergoing treatment for breast cancer. COVID-19 does not appear to be more frequent in patients undergoing treatment than in the general population. This study has just been made available on the scientific and medical publications servers MedRxic and HAL. 

Institut Curie - the leading breast cancer treatment center in France and in Europe - has put its teams to work to conduct a study on the relationship between COVID-19 and breast cancer. This is the first worldwide study involving women undergoing active breast cancer treatment and also infected by COVID-19. Remember that cancer patients were thus far considered to be at greater risk of serious forms of (and death from) COVID-19, based on Chinese studies that made no disctinction between cancer types. These results have yet to be fully explained. The scientific article published online today addresses the symptoms, characteristics and prognosis for patients suffering from breast cancer and undergoing treatment, and also presenting proven SARS-CoV-2 infection. Over 15,000 patients are currently undergoing active treatment (recieved over the past 4 months) for breast cancer in Institut Curie hospitals (Paris and Saint-Cloud). Only 59 patients have presented with proven COVID-19 infection, which seems to match the estimated frequency of positive cases throughout the French population (0.2-0.4%).

“Among the patients being treated for breast cancer and infected with COVID-19, we have to date sadly lost 4 patients,” explains Prof. François-Clément Bidard, oncologist. “According to our results, co-morbidity with pre-existing conditions (advanced age, diabetes, immune disorders, etc.) may alone explain these deaths.”

Furthermore, no association has been found between the severity of the disease and the type of anti-tumor treatment given (chemotherapy or other). Similarly, no increase in the severity of COVID-19 after radiotherapy on the breast or adjacent lymph nodes.

In total, COVID-19 does not appear to be more frequent than in the general population, and without any major apparent excess mortality in women undergoing treatment for breast cancer, which is good news.

Managing lockdown easing in an individualized manner

For women undergoing treatment, this type of study - combined with the use of approved serological tests - will allow us to manage the lockdown easing in an individualized manner, pending a future vaccine.

“For women who are currently presenting possible signs of cancer (for example recent appearance of a lump in the breast or armpit, whether or not it is painful), it is important to consult a physician and not delay treatment: not diagnosing and treating breast cancer in accordance with recommendations could be more dangerous to their health than COVID-19,” emphasizes Dr. Paul Cottu, a medical oncologist specializing in breast cancer and deputy head of the Department of medical oncology


These results will be available on MedRxiv and HAL and are currently submitted for review to a scientific journal.

This work was carried out after approval from Institut Curie’s review committee; they were fully funded by Institut Curie, with participation from professors of medicine from the University Paris-Saclay (UVSQ) and the University of Paris.

Authors of the study: Perrine Vuagnat, Maxime Frelaut, Toulsie Ramtohul, Clémence Basse, Sarah Diakite, Aurélien Noret, Audrey Bellesoeur, Vincent Servois, Delphine Hequet, Enora Laas, Youlia Kirova, Luc Cabel, Jean-Yves Pierga, Laurence Bozec, Xavier Paoletti, Paul Cottu, François-Clément Bidard

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